There is a known method of obtaining graphite powder, comprising the steps of grinding graphite material and its subsequent purification. Primary graphite formed in a blast furnace (Accepted Patent Application of Japan No. 6102528, published on Dec. 14, 1994), or graphite with a degree of purity below 95% (Accepted Patent Application of Japan No. 6102529, published on Dec. 14, 1994.) are used as graphite source material. Graphite material is ground under the action of instant unidirectional external forces either in a jet mill or in a crusher with high-speed blades. Graphite material is purified with hydrofluoric acid (Accepted Patent Application of Japan No. 6102529, published on Dec. 14, 1994), or with gaseous halogen at a high temperature (Accepted Patent Application of Japan No. 6045446, published on Jun. 15, 1994), or concentrated sulfuric acid (Accepted Patent Application of Japan No. 7014803, published on Feb. 22, 1995.).
The well-known method of obtaining graphite powder is complicated because of the hardware used. Low microhardness of graphite material requires the application of complex special devices and technologies for its grinding, and the use of highly corrosive media for graphite purification requires special chemical-proof equipment. The method of obtaining artificial graphite powder, including grinding carbon material and its graphitizing at a temperature of 2600-2700° C. (Accepted Patent Application of Japan No. 6021018, published on Mar. 23, 1994) is also known. Fresh coke is used as a source of carbon, with a hydrogen content of no less than 2%, or mixed with a carbonaceous substance in mesophase, which are treated after grinding with sulfuric or nitric acid, then washed with water, alkali or an organic solvent.
Artificial graphite powder obtained by well-known method is characterized by a modest degree of graphitization, i.e., degree of approximation of its structure to the perfect graphite structure, which is the reason for obtaining graphite of insufficient quality. This is attributable to the fact that when fine-grinding the above source carbon materials, the elements of crystal structure are destroyed, i.e., amorphization occurs. Hence, the graphitizing ability of initial carbon materials is reduced, resulting in obtaining artificial graphite of modest quality, whose structure is far from perfect graphite structure. The defects in the structure of artificial graphite powder obtained by the well-known methods are also caused by residual impurities present in coke. In addition, the well-known method is complex because of hardware used, as it requires special equipment resistant to the attack of strong acids and alkalis.